Short-term and Long-term Outcomes of Moxifloxacin Compared to Standard Antibiotic Treatment in Acute Exacerbations of Chronic Bronchitis

Study objectives To compare the effectiveness of oral moxifloxacin with standard antibiotic therapy in acute exacerbation of chronic bronchitis (AECB). Design Multicenter, multinational, randomized, double-blind study of two parallel treatment arms. Patients Outpatients ≥ 45 years old with stable chronic bronchitis, smoking history of ≥ 20 pack-years, two or more AECBs in the previous year, and FEV 1 Interventions Randomization (stratified on steroid use) between moxifloxacin (400 mg qd for 5 days) and standard therapy (amoxicillin [500 mg tid for 7 days], clarithromycin [500 mg bid for 7 days], or cefuroxime-axetil [250 mg bid for 7 days]). Measurements Assessment at enrollment, randomization (Anthonisen type 1 exacerbation), 7 to 10 days after treatment, and monthly until next AECB or up to 9 months. The primary efficacy variable was clinical success (sufficient improvement, no alternative antimicrobial therapy required) 7 to 10 days after therapy. Secondary predefined end points were clinical cure (return to pre-exacerbation status), further antimicrobial use, time to next AECB, and bacteriologic success. Results Three hundred fifty-four patients received moxifloxacin, and 376 patients received standard therapy. At 7 to 10 days after therapy, clinical success rates were similar in intention-to-treat (ITT) patients (95% confidence interval [CI], − 0.7 to 9.5) and per-protocol (PP) patients (95% CI, − 3.0 to 8.5). Moxifloxacin showed superior clinical cure rates over standard therapy in both ITT patients (95% CI, 1.4 to 14.9) and PP patients (95% CI, 0.3 to 15.6), and higher bacteriologic success in microbiologically valid patients (95% CI, 0.4 to 22.1). Fewer ITT patients required antimicrobials after treatment with moxifloxacin than standard therapy (p Conclusions Moxifloxacin was equivalent to standard therapy for clinical success and showed superiority over standard therapy in clinical cure, bacteriologic eradication, and long-term outcomes.